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Even after they settle down to breed, gannets remain noisy and demonstrative birds. Pairs engage in strange greetings each time a partner returns, usually involving much neck rubbing and
clashing of bills, an activity known as "scissoring". At other times they will gently nibble each other's neck, indulge in elaborate bowing or point their bills skyward. These rituals continue throughout the
nesting season and are usually regarded as a means of reinforcing the bond between male and female. While most birds develop a special brood patch of bare skin on the breast to warm their eggs, the adult gannet covers
its egg with its large webbed feet, placing one on top of the other. The egg is incubated in turn by both male and female for periods lasting 30 or more hours. During its absence the off-duty bird may fly up to 400
miles in search of food. The chick hatches black, naked and blind after 44 days, but soon grows an insulating coat of fluffy white down. It feeds by plunging its head inside its parent's throat where partly-digested
fish forms a rich diet. It opens its eyes after eight days, starts growing feathers after three weeks and can fly about three months after hatching. Some 25 per cent of pairs fail to rear young each year. Of the
youngsters that survive to leave the colony, only a third will learn to fish, make the long journey to the coasts of West Africa and
 survive the first year. Those that do so, however, are well
equipped for life; they have a good chance of living to the age of five and returning to one of the colonies to breed. Gannets have been known to live as long as 21 years, and some are doubtless older.
For generations men have regularly scaled the cliffs of the Scottish gannetries to collect the fat youngsters before they fly in early September. In the 12th century there was
even a dispute between the laird of the Bass Rock in the Firth of Forth and the nuns of North Berwick over barrels of fat collected by boiling up young gannets - gugas in Gaelic.
Today gugas are still harvested under licence by Lewismen on Sula Sgeir where several thousand are taken annually, plucked, singed over a peat fire, skinned, gutted and salted to
provide winter food. During the first 60 years of the 19th century the gannet population was halved, but by 1880 the birds of Ailsa Craig had been left in peace and their numbers had
begun to grow once more. In 1905 there were 3500 pairs; by the mid-1980s the population had increased to 22,800 pairs. Yet the gannetry on Ailsa Craig is unusual in that
the number of pairs present in a given year is, inexplicably, subject to violent fluctuations. In the past the cliffs have been described as "fully occupied", yet the number of gannets has
continued to grow. To date they have not managed to colonise the top of the island, probably because of the presence of rats; it is doubtful that they ever will. About 50 per
cent of the total population of North Atlantic gannets (254,600 birds) breed in Scotland, and almost 60 per cent of those in the eastern Atlantic (223,400 birds). The gannetries on
Ailsa Craig and the Bass Rock are the best known and most accessible. The solan goose may no longer be the gastronomic delight it once was, but it is still an important part of Scotland's heritage. |
